A healthy planet needs healthy forests. Thriving forests regulate the water cycle and stabilize soils. Forests also help moderate climate by soaking up and storing carbon dioxide. In addition to these ecosystem services, forests provide habitat for diverse flora and fauna, offer cultural, spiritual, and recreational opportunities, and provide a variety of food, medicines, and wood.

Nearly 4 billion hectares of forest cover the earth’s surface, roughly 30 percent of its total land area. Though extensive, the world’s forests have shrunk by some 40 percent since agriculture began 11,000 years ago. Three quarters of this loss occurred in the last two centuries as land was cleared to make way for farms and to meet demand for wood.

Over the last five years, the world suffered a net loss of some 37 million hectares (91 million acres) of forest, according to data from the United Nations Food and Agriculture Organization. This number reflects the felling of 64.4 million hectares of trees and the planting or natural regeneration of 27.8 million hectares of new forest. Each year the world loses some 7.3 million hectares of forest, an area the size of Panama. Due to extensive reforestation, this net forest shrinkage has slowed slightly from the 8.9 million hectares lost annually in the 1990s. While this is encouraging, it obscures the sobering fact that gross deforestation has not declined significantly since 2000.

Forest degradation is also cause for concern. Of the world’s 1.4 billion hectares of remaining primary forest—natural forest that shows no sign of human impact—6 million hectares are lost or degraded each year. We are losing not only forest area but some of our best forest stands.

Africa lost 64 million hectares of forest between 1990 and 2005, the greatest decline of any continent. (See Data.) Fuelwood gathering drives much of this forest depletion. Timber exports also play a role, with 80 percent of the Congo Basin’s timber production being exported, mainly to China and the European Union.

South America has sustained the second greatest forest loss since 1990—59 million hectares—and deforestation has accelerated somewhat over the last five years, from 3.8 million hectares a year in the 1990s to 4.3 million hectares annually since 2000. This recent acceleration reflects Brazil’s reported net loss of 16 million hectares between 2000 and 2005—three fourths of the regional total. If Amazonian deforestation continues unchecked, the world’s largest rainforest will be cut down to 60 percent of its current size by 2050.

Asia lost a net 8 million hectares in the 1990s but gained a net 5 million hectares between 2000 and 2005. This reversal is due to a massive reforestation effort in China, which reported planting 20 million hectares of trees between 2000 and 2005, with more than a third of this area in plantations. This growth rate, more than double that of the previous decade, is largely a result of China’s logging ban, a policy enacted after widespread deforestation in the upper reaches of the Yangtze River valley left the countryside vulnerable to severe floods in 1998.

Unfortunately, China’s tree cutting ban has simply driven deforestation elsewhere, as China continues to be the world’s largest wood importer and processor. South and Southeast Asia lost over 14 million hectares of forest in the last five years. Indonesia’s natural forests, losing 2 million hectares a year, have suffered some of the heaviest cutting and could disappear within 10 years as they give way to timber and oil-palm plantations.

Apart from China, most of the gains in forest area are in industrial countries, while developing countries bear the brunt of deforestation. Forest area in North America has been stable at roughly 675 million hectares for the past 15 years, with deforestation in Mexico largely offsetting new plantings and reforestation in the United States. Central America has lost over 5 million hectares since 1990, and Europe has gained 12 million hectares. Industrial countries may be leading the way in conserving their own forests, but their demand for wood drives much of the deforestation elsewhere on the globe.

Forests are cleared to grow food and energy crops, graze cattle, and meet demand for wood products. The global wood harvest totaled 3.4 billion cubic meters in 2004, up from 2.3 billion cubic meters in 1961. Fifty-two percent of this is used as fuel, though this varies regionally. (See Data.) Fuelwood accounts for 89 percent of Africa’s wood harvest, where it is often the only accessible and affordable source of energy for heating and cooking, but only 17 percent in North and Central America, where other energy sources are more readily available.

Much of the world’s wood is harvested illegally. Illegal logging accounts for more than half of timber production in Russia, Indonesia, Brazil, and Cameroon. In addition to devastating forest ecosystems, illegal logging robs forest dwellers of their livelihoods, fuels social turmoil, and deprives timber-producing countries of up to $15 billion of revenue each year.

Forest plantations—planted stands that often consist of single-age monocultures—can alleviate logging pressure on natural forest areas. Worldwide, plantations account for less than 5 percent of global forest area but produce roughly 35 percent of the annual wood harvest. Growth in plantation area has accelerated, increasing by 2.8 million hectares a year since 2000. By 2020, plantation production is projected to meet 44 percent of global wood demand. Close to half of the world’s productive plantations are located in China, Russia, and the United States. Still, plantations cannot offer the same biodiversity and vitality that a natural forest can. Plantation development is most advantageous on lands that are already clear of trees, as a way to offset future deforestation and decrease pressure on natural stands to supply forest products.

Reducing consumption of virgin wood products is integral to protecting the world’s remaining natural forests. This entails curbing the world’s appetite for timber, paper, and other wood products and decreasing wood burning for fuel by developing energy alternatives. In addition, stepping up recycling efforts will temper the need to fell more trees.

Certification emerged more than a decade ago as a way to identify forests that are managed and logged responsibly. Sustainable forestry depends on shifting from clearcutting to selective cutting of mature trees while maintaining the social and economic benefits enjoyed by forest inhabitants and other stakeholders. As of early 2006, the Forest Stewardship Council, the world’s most rigorous accreditation organization, had certified some 68 million hectares in 66 countries as sustainable. Certification has expanded considerably in the past five years, although certified wood products still constitute only a small fraction of the global market.

For consumers, demanding certified wood products spur responsible forest management and help curb illegal logging. If governments, as policymakers and forest product consumers themselves, were to take a stronger leadership role in forest management oversight and enforcement, this would also encourage sustainable forestry practices. Protecting the world’s remaining natural forests, cultivating new forest stands, and reducing consumption of forest resources are all critical steps toward preserving the indispensable services that forests provide. It is in our best interest to keep forests flourishing.